I did successfully install Ubuntu 7.04 ("feisty") on a Playstation 3.
Once you have Ubuntu installed you can use the standard package
management tools for Debian/Ubuntu to install the r-base-core,
r-recommended and r-base-dev packages. Those packages are for R-2.4.1
but I had no trouble installing and checking the most recent versions
of R from the SVN site.

Essentially the Playstation 3 becomes a typical Ubuntu system with all
the tools from Ubuntu. At present X11 uses the framebuffer device so
the graphics is poor by X11 standards and very poor by gamer's
standards.

Overall it is quite amazing given that the PS3 with a 60GB hard drive
is now being sold in the U.S. for $500 and that includes a Blu-ray DVD
drive and full 1080p HDMI interface. At $500 it is one of the
cheapest Blu-ray DVD players, which is what I bought it for. It's
great to be able to run R on my DVD player.